1. Field of the Invention
The present invention relates generally to securing transactional data and, more particularly, to securing transactional data without the use of chemical battery cells by using a secondary data path.
2. Description of the Related Art
A host computer executes a plurality of applications, such as banking software, database software, or any other data changing application. An application running on the host computer processes various types of data, including highly sensitive data. The transactional data from the host application is processed using cache memory and after successful processing is permanently stored on disk or tape. When a host application shuts down normally, the transactional data associated with the application is completely processed and is moved from the cache memory to permanent storage before the application actually shuts down. As a result, there is no incomplete data in cache memory that still needs to be processed. If, however, an unexpected power failure occurs during execution of a host application, the host application might not have the opportunity to completely process the data and move the data to permanent storage. Instead, there might be incomplete transactional data still left in the cache memory. In order to not lose any transactional data from a host application, conventional architecture place the cache memory devices in a low-power operational state called ‘self-refresh’ mode. During this phase, the cache memory devices are powered using a chemical cell to protect the data in the cache memory until power is restored to the system.
The usage of chemical cells has its own disadvantages and limitations. For one, a chemical cell has limited shelf life and needs to be monitored periodically and replaced when the cell's useful life has expired. In order to replace the chemical cell, the whole system needs to be shut down and the chemical cell replaced. This would result in considerable down time of the system, which would be inconvenient and undesirable. Further, chemical cells need to be properly handled and disposed leading to additional costs and undesirable overhead.
It would, therefore, be desirable to find an alternate solution of preserving the transactional data without having to periodically monitor and maintain the chemical cell.
It is in this context that embodiments of the invention arise.